How 'F Scale' measures tornado strength

Tulsa World-Fujita-scale forum: In 1999, Texas Tech University's Wind Science and Engineering Research Center proposed an official examination of the problem that could be used to create an enhanced F-scale meeting the needs of the 'meteorological and engineering communities.'

Shelters and safe rooms routinely are tested to withstand storms of various intensities. The force of a storm usually is measured on the "F scale."

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Fujita-scale forum: In 1999, Texas Tech University's Wind Science and Engineering Research Center proposed an official examination of the problem that could be used to create an enhanced F-scale meeting the needs of the "meteorological and engineering communities." A Fujita-Scale Forum of 23 scale users, led by Texas Tech's Kishor Mehta and Jim McDonald, met in March 2001 and developed the "Enhanced Fujita Scale," publishing its recommendations in June 2004. The "Enhanced Fujita Scale (EF Scale) was implemented nationwide Feb. 1, 2007.

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